Nanomaterials2016, 6(7), 125; doi:10.3390/nano6070125 (registering DOI) - published 25 June 2016 Show/Hide Abstract
Abstract: The development of smart nanocarriers for the delivery of therapeutic drugs has experienced considerable expansion in recent decades, with the development of new medicines devoted to cancer treatment. In this respect a wide range of strategies can be developed by employing liposome nanocarriers with desired physico-chemical properties that, by exploiting a combination of a number of suitable soft interactions, can facilitate the transit through the biological barriers from the point of administration up to the site of drug action. As a result, the materials engineer has generated through the bottom up approach a variety of supramolecular nanocarriers for the encapsulation and controlled delivery of therapeutics which have revealed beneficial developments for stabilizing drug compounds, overcoming impediments to cellular and tissue uptake, and improving biodistribution of therapeutic compounds to target sites. Herein we present recent advances in liposome drug delivery by analyzing the main structural features of liposome nanocarriers which strongly influence their interaction in solution. More specifically, we will focus on the analysis of the relevant soft interactions involved in drug delivery processes which are responsible of main behaviour of soft nanocarriers in complex physiological fluids. Investigation of the interaction between liposomes at the molecular level can be considered an important platform for the modeling of the molecular recognition processes occurring between cells. Some relevant strategies to overcome the biological barriers during the drug delivery of the nanocarriers are presented which outline the main structure-properties relationships as well as their advantages (and drawbacks) in therapeutic and biomedical applications.
Nanomaterials2016, 6(7), 124; doi:10.3390/nano6070124 - published 24 June 2016 Show/Hide Abstract
Abstract: Micro- and nano-patterning/modification are emerging strategies to improve surfaces properties that may influence critically cells adherence and differentiation. Aim of this work was to study the in vitro biological reactivity of human bone marrow mesenchymal stem cells (hBMSCs) to a nanostructured titanium dioxide (TiO2) surface in comparison to a coverglass (Glass) in two different culture conditions: with (osteogenic medium (OM)) and without (proliferative medium (PM)) osteogenic factors. To evaluate cell adhesion, hBMSCs phosphorylated focal adhesion kinase (pFAK) foci were analyzed by confocal laser scanning microscopy (CLSM) at 24 h: the TiO2 surface showed a higher number of pFAK foci with respect to Glass. The hBMSCs differentiation to osteoblasts was evaluated in both PM and OM culture conditions by enzyme-linked immunosorbent assay (ELISA), CLSM and real-time quantitative reverse transcription PCR (qRT-PCR) at 28 days. In comparison with Glass, TiO2 surface in combination with OM conditions increased the content of extracellular bone proteins, calcium deposition and alkaline phosphatase activity. The qRT-PCR analysis revealed, both in PM and OM, that TiO2 surface increased at seven and 28 days the expression of osteogenic genes. All together, these results demonstrate the capability of TiO2 nanostructured surface to promote hBMSCs osteoblast differentiation and its potentiality in biomedical applications.
Nanomaterials2016, 6(7), 120; doi:10.3390/nano6070120 (registering DOI) - published 24 June 2016 Show/Hide Abstract
Abstract: The mechanical properties of silicene nanostructures subject to tensile loading were studied via a molecular dynamics (MD) simulation. The effects of temperature on Young’s modulus and the fracture strain of silicene with armchair and zigzag types were examined. The maximum in-plane stress and the corresponding critical strain of the armchair and the zigzag silicene sheets at 300 K were 8.85 and 10.62, and 0.187 and 0.244 N/m, respectively. The in-plane stresses of the silicene sheet in the armchair direction at the temperatures of 300, 400, 500, and 600 K were 8.85, 8.50, 8.26, and 7.79 N/m, respectively. The in-plane stresses of the silicene sheet in the zigzag direction at the temperatures of 300, 400, 500, and 600 K were 10.62, 9.92, 9.64, and 9.27 N/m, respectively. The improved mechanical properties can be calculated in a silicene sheet yielded in the zigzag direction compared with the tensile loading in the armchair direction. The wrinklons and waves were observed at the shear band across the center zone of the silicene sheet. These results provide useful information about the mechanical and fracture behaviors of silicene for engineering applications.
Nanomaterials2016, 6(7), 121; doi:10.3390/nano6070121 - published 23 June 2016 Show/Hide Abstract
Abstract: Highly orientated polypyrrole (PPy)–coated polyacrylonitrile (PAN) (PPy–PAN) nanofiber yarn was prepared with an electrospinning technique and in-situ chemical polymerization. The morphology and chemical structure of PPy–PAN nanofiber yarn was characterized by scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and fourier transform infrared spectroscopy (FTIR), which indicated that the PPy as the shell layer was homogeneously and uniformly polymerized on the surface of PAN nanofiber. The effects of different concentration of doping acid on the responses of PPy–PAN nanofiber yarn sensor were investigated. The electrical responses of the gas sensor based on the PPy–PAN nanofiber yarn to ammonia were investigated at room temperature. The nanoyarn sensor composed of uniaxially aligned PPy–PAN nanofibers with a one-dimensional structure exhibited a transient response, and the response time was less than 1 s. The excellent sensing properties mentioned above give rise to good potential application prospects in the field of ammonia sensor.
Nanomaterials2016, 6(7), 122; doi:10.3390/nano6070122 - published 23 June 2016 Show/Hide Abstract
Abstract: With the recent advances in nanotechnology, plasma nanofabrication has become an exciting new niche because plasma-based approaches can deliver unique structures at the nanoscale that cannot be achieved by other techniques and/or in a more economical and environmentally friendly manner.[...]
Nanomaterials2016, 6(7), 123; doi:10.3390/nano6070123 - published 23 June 2016 Show/Hide Abstract
Abstract: Nanoscience emerged in the last decades of the 20th century with the general aim to determine those properties that appear when small particles of nanometric dimensions are prepared and stabilized.[...]